Welcome to the latest Bugle that focuses upon body perception, so often affected in CRPS. Body perception should form part of the assessment in my view, as the construction of this sense by the brain is a feature of the condition and must be addressed.
Evaluation of a prototype tool for communicating body perception disturbances in complex regional pain syndrome
Ailie J. Turton, Mark Palmer, Sharon Grieve, Timothy P. Moss, Jenny Lewis and Candida S. McCabe
Patients with Complex Regional Pain Syndrome (CRPS) experience distressing changes in body perception. However representing body perception is a challenge. A digital media tool for communicating body perception disturbances was developed. A proof of concept study evaluating the acceptability of the application for patients to communicate their body perception is reported in this methods paper. Thirteen CRPS participants admitted to a 2-week inpatient rehabilitation program used the application in a consultation with a research nurse. Audio recordings were made of the process and a structured questionnaire was administered to capture experiences of using the tool. Participants produced powerful images of disturbances in their body perception. All reported the tool acceptable for communicating their body perception. Participants described the positive impact of now seeing an image they had previously only imagined and could now convey to others. The application has provided a novel way for communicating perceptions that are otherwise difficult to convey.
* Full article available on the Frontiers in Human Neuroscience website – click here
Eur J Pain. 2012 Oct;16(9):1320-30
Perceptions of the painful body: the relationship between body perception disturbance, pain and tactile discrimination in complex regional pain syndrome.
Lewis JS, Schweinhardt P.
Disturbances in body perception are increasingly acknowledged as a feature of complex regional pain syndrome (CRPS). Conventional treatments have limited success particularly among those with long-standing disease. Understanding the relationship between body perception disturbance, pain and tactile acuity might provide insight into alternative avenues for treatment. The aim of this study was to test the hypotheses that (1) body perception disturbance is positively related to pain and (2) decreased tactile acuity is related to increased body perception disturbance.
A controlled observational design was used to measure these features among those with CRPS of one arm. The extent of body perception disturbance was assessed using the Bath CRPS body perception disturbance scale and pain was measured using the neuropathic pain symptom inventory. Two-point discrimination threshold testing was performed as a measure of tactile acuity.
Findings confirmed both hypotheses. Body perception disturbance was found to positively correlate with pain such that those in greater pain had more extensive body perception disturbance (r = 0.57, p < 0.01). Furthermore, a positive correlation was revealed between body perception disturbance and two-point discrimination thresholds (r = 0.5, p < 0.025) so those with greater body perception disturbance had worse tactile acuity. Interestingly, those with longer disease duration had significantly greater body perception disturbance (r = 0.66, p < 0.001).
Aberrant central processing is suggested as the neural correlate of body perception disturbance and tactile impairment. The exact relationship between body perception disturbance, pain and tactile acuity and how they may be modulated for pain relief requires further exploration.
Pain. 2012 Nov;153(11):2174-81
Impaired spatial body representation in complex regional pain syndrome type 1 (CRPS I).
Reinersmann A, Landwehrt J, Krumova EK, Ocklenburg S, Güntürkün O, Maier C.
Recently, a shift of the visual subjective body midline (vSM), a correlate of the egocentric reference frame, towards the affected side was reported in patients with complex regional pain syndrome (CRPS). However, the specificity of this finding is as yet unclear. This study compares 24 CRPS patients to 21 patients with upper limb pain of other origin (pain control) and to 24 healthy subjects using a comprehensive test battery, including assessment of the vSM in light and dark, line bisection, hand laterality recognition, neglect-like severity symptoms, and motor impairment (disability of the arm, shoulder, and hand). Statistics: 1-way analysis of variance, t-tests, significance level: 0.05. In the dark, CRPS patients displayed a significantly larger leftward spatial bias when estimating their vSM, compared to pain controls and healthy subjects, and also reported lower motor function than pain controls. For right-affected CRPS patients only, the deviation of the vSM correlated significantly with the severity of distorted body perception. Results confirm previous findings of impaired visuospatial perception in CRPS patients, which might be the result of the involvement of supraspinal mechanisms in this pain syndrome. These mechanisms might accentuate the leftward bias that results from a right-hemispheric dominance in visuospatial processing and is known as pseudoneglect. Pseudoneglect reveals itself in the tendency to perceive the midpoint of horizontal lines or the subjective body midline left of the centre. It was observable in all 3 groups, but most pronounced in CRPS patients, which might be due to the cortical reorganisation processes associated with this syndrome.